Dear Sirs
I need a help in solving a problem with a "halt -p" disorder which I encountered on my Presario CQ60 laptop.
My OS is OpenBSD 4.6.
When I need to shutdown and power off my system I use a ' shutdown -hp now' or 'halt -p' commands from the shell prompt. But the results are ambiguous: sometimes it really shuts down and power-offs and sometimes it just restarts.
Can you give me a hint, please, on how to make it so that when I type 'halt -p' my machine will always completely stop and turn its lights off?

Theo has frequently stated that the choice between ACPI and APM is dependant on a few internal heuristics.. this system does indeed appear to be newer, and probably is defaulting to ACPI not APM, but ocicat is correct that the user could have offered a little more.. including a dmesg.

Another thing that dmesg(8) output would show is the BIOS version. Depending upon what could be ferreted out on HP's Website, there may or may not be a newer version available. Upgrading the BIOS may also help in resolving shutdown problems.

In looking at HP's Website, I get 300 hits when looking for "Presario CQ60". In order to find out whether there is a newer BIOS available for your system, you need to look yourself. Having the SKU number found on the model tag will help.

If you find that a newer BIOS is available, I would recommend installing it first. This may or may not resolve your shutdown(8) problems, but it will be a step in the right direction.

If installing a newer BIOS does not resolve the problem, you may want to temporarily disable acpi(4). Information on how to temporarily disable drivers or permanently disable drivers can be found in Section 5.9 of the FAQ. This also may or may not fix the problem.

You may want to experiment with the SP kernel to see if the same problem occurs with this kernel. Yes, I can understand why you might not want to use a single-processor kernel with a multi-core processor. Information on booting different kernels can be found in the boot(8) manpage & Section 5.8 of the FAQ.

There has been a rash of acpi(4) problems on Hewlett-Packard hardware of late. Whoever is designing this hardware is not following the ACPI standard. An example thread on the official misc@ mailing list can be found at the following:

As seen here, work on acpi(4) is going on this week at the c2k10 hackathon. For these reasons, I agree with BSDfan666's suggestion of installing a -current snapshot & test. Because the hackathon is going on now, it may be worth waiting a few weeks for the CVS tree to settle down before trying -current. Trying 4.7-release is another option, but trying the latest code will be of more interest to the developers if you later choose to escalate the problem to them in a problem report.